Fix MR "Changes" diff note up arrow to edit last note

Fix https://gitlab.com/gitlab-org/gitlab-ce/issues/33868

While in a MR "Changes" tab looking at some diff note discussions.
Clicking reply and pressing the up-arrow should edit your last comment in
that discussion.

I suspect this regressed in
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/11173/diffs#f4bb984ec495c5cb58516785c62978f5209c39b4_179_178
where we changed the selector

app/assets/javascripts/notes.js

@@ -187,7 +187,7 @@ const normalizeNewlines = function(str) {
           if ($textarea.val() !== '') {
             return;
           }
-          myLastNote = $(`li.note[data-author-id='${gon.current_user_id}'][data-editable]:last`, $textarea.closest('.note, #notes'));
+          myLastNote = $(`li.note[data-author-id='${gon.current_user_id}'][data-editable]:last`, $textarea.closest('.note, .notes_holder, #notes'));
           if (myLastNote.length) {
             myLastNoteEditBtn = myLastNote.find('.js-note-edit');
             return myLastNoteEditBtn.trigger('click', [true, myLastNote]);

spec/javascripts/fixtures/merge_requests.rb

@@ -55,13 +55,20 @@ describe Projects::MergeRequestsController, '(JavaScript fixtures)', type: :cont
     render_merge_request(example.description, merge_request)
   end
 
+  it 'merge_requests/changes_tab_with_comments.json' do |example|
+    create(:diff_note_on_merge_request, project: project, author: admin, position: position, noteable: merge_request)
+    create(:note_on_merge_request, author: admin, project: project, noteable: merge_request)
+    render_merge_request(example.description, merge_request, action: :diffs, format: :json)
+  end
+
   private
 
-  def render_merge_request(fixture_file_name, merge_request)
-    get :show,
+  def render_merge_request(fixture_file_name, merge_request, action: :show, format: :html)
+    get action,
       namespace_id: project.namespace.to_param,
       project_id: project,
-      id: merge_request.to_param
+      id: merge_request.to_param,
+      format: format
 
     expect(response).to be_success
     store_frontend_fixture(response, fixture_file_name)

spec/javascripts/merge_request_notes_spec.js

@@ -7,16 +7,20 @@ import '~/render_gfm';
 import '~/render_math';
 import '~/notes';
 
+const upArrowKeyCode = 38;
+
 describe('Merge request notes', () => {
   window.gon = window.gon || {};
   window.gl = window.gl || {};
   gl.utils = gl.utils || {};
 
-  const fixture = 'merge_requests/diff_comment.html.raw';
-  preloadFixtures(fixture);
+  const discussionTabFixture = 'merge_requests/diff_comment.html.raw';
+  const changesTabJsonFixture = 'merge_requests/changes_tab_with_comments.json';
+  preloadFixtures(discussionTabFixture, changesTabJsonFixture);
 
+  describe('Discussion tab with diff comments', () => {
     beforeEach(() => {
-    loadFixtures(fixture);
+      loadFixtures(discussionTabFixture);
       gl.utils.disableButtonIfEmptyField = _.noop;
       window.project_uploads_path = 'http://test.host/uploads';
       $('body').data('page', 'projects:merge_requests:show');
@@ -28,7 +32,7 @@ describe('Merge request notes', () => {
     describe('up arrow', () => {
       it('edits last comment when triggered in main form', () => {
         const upArrowEvent = $.Event('keydown');
-      upArrowEvent.which = 38;
+        upArrowEvent.which = upArrowKeyCode;
 
         spyOnEvent('.note:last .js-note-edit', 'click');
 
@@ -39,7 +43,7 @@ describe('Merge request notes', () => {
 
       it('edits last comment in discussion when triggered in discussion form', (done) => {
         const upArrowEvent = $.Event('keydown');
-      upArrowEvent.which = 38;
+        upArrowEvent.which = upArrowKeyCode;
 
         spyOnEvent('.note-discussion .js-note-edit', 'click');
 
@@ -58,4 +62,38 @@ describe('Merge request notes', () => {
         });
       });
     });
+  });
+
+  describe('Changes tab with diff comments', () => {
+    beforeEach(() => {
+      const diffsResponse = getJSONFixture(changesTabJsonFixture);
+      const noteFormHtml = `<form class="js-new-note-form">
+        <textarea class="js-note-text"></textarea>
+      </form>`;
+      setFixtures(diffsResponse.html + noteFormHtml);
+      $('body').data('page', 'projects:merge_requests:show');
+      window.gon.current_user_id = $('.note:last').data('author-id');
+
+      return new Notes('', []);
+    });
+
+    describe('up arrow', () => {
+      it('edits last comment in discussion when triggered in discussion form', (done) => {
+        const upArrowEvent = $.Event('keydown');
+        upArrowEvent.which = upArrowKeyCode;
+
+        spyOnEvent('.note:last .js-note-edit', 'click');
+
+        $('.js-discussion-reply-button').trigger('click');
+
+        setTimeout(() => {
+          $('.js-note-text').trigger(upArrowEvent);
+
+          expect('click').toHaveBeenTriggeredOn('.note:last .js-note-edit');
+
+          done();
+        });
+      });
+    });
+  });
 });